Subband structure of a two-dimensional electron gas formed at the polar surface of the strong spin-orbit perovskite KTaO3

P. D. C. King; R. H. He; T. Eknapakul; P. Buaphet; S-K Mo; Y. Kaneko; S. Harashima; Y. Hikita; M. S. Bahramy; C. Bell; Z. Hussain; Y. Tokura; Z-X Shen; H. Y. Hwang; F. Baumberger; W. Meevasana

doi:10.1103/PhysRevLett.108.117602

Subband structure of a two-dimensional electron gas formed at the polar surface of the strong spin-orbit perovskite KTaO₃

P. D. C. King, R. H. He, T. Eknapakul, P. Buaphet, S-K Mo, Y. Kaneko, S. Harashima, Y. Hikita, M. S. Bahramy, C. Bell, Z. Hussain, Y. Tokura, Z-X Shen, H. Y. Hwang, F. Baumberger, W. Meevasana

Research output: Contribution to journal › Article › peer-review

183 Citations (Scopus)

5 Downloads (Pure)

Abstract

We demonstrate the formation of a two-dimensional electron gas (2DEG) at the (100) surface of the 5d transition-metal oxide KTaO3. From angle-resolved photoemission, we find that quantum confinement lifts the orbital degeneracy of the bulk band structure and leads to a 2DEG composed of ladders of subband states of both light and heavy carriers. Despite the strong spin-orbit coupling, our measurements provide a direct upper bound for the potential Rashba spin splitting of only Delta k(parallel to) similar to 0.02 angstrom(-1) at the Fermi level. The polar nature of the KTaO₃(100) surface appears to help mediate the formation of the 2DEG as compared to nonpolar SrTiO₃(100).

Original language	English
Article number	117602
Number of pages	5
Journal	Physical Review Letters
Volume	108
Issue number	11
DOIs	https://doi.org/10.1103/PhysRevLett.108.117602
Publication status	Published - 14 Mar 2012

Access to Document

10.1103/PhysRevLett.108.117602

king2012physrevlett117602
© 2012 American Physical Society
Final published version, 444 KB

Fellowship - Unspent EPSRC Balance: Fellowship - Unspent Funds
King, P. (PI)
EPSRC
1/10/11 → 31/03/12
Project: Fellowship
Topological Protection and NonEquilibriu: Topological Protection and NonEquilibrium States in Strongly Correlated Electron Systems
Wahl, P. (PI), Baumberger, F. (CoI), Davis, J. C. (CoI), Green, A. (CoI), Hooley, C. (CoI), Keeling, J. M. J. (CoI) & Mackenzie, A. (CoI)
EPSRC
1/09/11 → 31/08/17
Project: Standard

Cite this

King, P. D. C., He, R. H., Eknapakul, T., Buaphet, P., Mo, S.-K., Kaneko, Y., Harashima, S., Hikita, Y., Bahramy, M. S., Bell, C., Hussain, Z., Tokura, Y., Shen, Z.-X., Hwang, H. Y., Baumberger, F., & Meevasana, W. (2012). Subband structure of a two-dimensional electron gas formed at the polar surface of the strong spin-orbit perovskite KTaO₃. Physical Review Letters, 108(11), Article 117602. https://doi.org/10.1103/PhysRevLett.108.117602

@article{90bccd9cf7424fdc9d9855f01406b1d4,

title = "Subband structure of a two-dimensional electron gas formed at the polar surface of the strong spin-orbit perovskite KTaO3",

abstract = "We demonstrate the formation of a two-dimensional electron gas (2DEG) at the (100) surface of the 5d transition-metal oxide KTaO3. From angle-resolved photoemission, we find that quantum confinement lifts the orbital degeneracy of the bulk band structure and leads to a 2DEG composed of ladders of subband states of both light and heavy carriers. Despite the strong spin-orbit coupling, our measurements provide a direct upper bound for the potential Rashba spin splitting of only Delta k(parallel to) similar to 0.02 angstrom(-1) at the Fermi level. The polar nature of the KTaO3(100) surface appears to help mediate the formation of the 2DEG as compared to nonpolar SrTiO3(100).",

author = "King, {P. D. C.} and He, {R. H.} and T. Eknapakul and P. Buaphet and S-K Mo and Y. Kaneko and S. Harashima and Y. Hikita and Bahramy, {M. S.} and C. Bell and Z. Hussain and Y. Tokura and Z-X Shen and Hwang, {H. Y.} and F. Baumberger and W. Meevasana",

year = "2012",

month = mar,

day = "14",

doi = "10.1103/PhysRevLett.108.117602",

language = "English",

volume = "108",

journal = "Physical Review Letters",

issn = "0031-9007",

publisher = "American Physical Society",

number = "11",

}

King, PDC, He, RH, Eknapakul, T, Buaphet, P, Mo, S-K, Kaneko, Y, Harashima, S, Hikita, Y, Bahramy, MS, Bell, C, Hussain, Z, Tokura, Y, Shen, Z-X, Hwang, HY, Baumberger, F & Meevasana, W 2012, 'Subband structure of a two-dimensional electron gas formed at the polar surface of the strong spin-orbit perovskite KTaO₃', Physical Review Letters, vol. 108, no. 11, 117602. https://doi.org/10.1103/PhysRevLett.108.117602

TY - JOUR

T1 - Subband structure of a two-dimensional electron gas formed at the polar surface of the strong spin-orbit perovskite KTaO3

AU - King, P. D. C.

AU - He, R. H.

AU - Eknapakul, T.

AU - Buaphet, P.

AU - Mo, S-K

AU - Kaneko, Y.

AU - Harashima, S.

AU - Hikita, Y.

AU - Bahramy, M. S.

AU - Bell, C.

AU - Hussain, Z.

AU - Tokura, Y.

AU - Shen, Z-X

AU - Hwang, H. Y.

AU - Baumberger, F.

AU - Meevasana, W.

PY - 2012/3/14

Y1 - 2012/3/14

N2 - We demonstrate the formation of a two-dimensional electron gas (2DEG) at the (100) surface of the 5d transition-metal oxide KTaO3. From angle-resolved photoemission, we find that quantum confinement lifts the orbital degeneracy of the bulk band structure and leads to a 2DEG composed of ladders of subband states of both light and heavy carriers. Despite the strong spin-orbit coupling, our measurements provide a direct upper bound for the potential Rashba spin splitting of only Delta k(parallel to) similar to 0.02 angstrom(-1) at the Fermi level. The polar nature of the KTaO3(100) surface appears to help mediate the formation of the 2DEG as compared to nonpolar SrTiO3(100).

AB - We demonstrate the formation of a two-dimensional electron gas (2DEG) at the (100) surface of the 5d transition-metal oxide KTaO3. From angle-resolved photoemission, we find that quantum confinement lifts the orbital degeneracy of the bulk band structure and leads to a 2DEG composed of ladders of subband states of both light and heavy carriers. Despite the strong spin-orbit coupling, our measurements provide a direct upper bound for the potential Rashba spin splitting of only Delta k(parallel to) similar to 0.02 angstrom(-1) at the Fermi level. The polar nature of the KTaO3(100) surface appears to help mediate the formation of the 2DEG as compared to nonpolar SrTiO3(100).

U2 - 10.1103/PhysRevLett.108.117602

DO - 10.1103/PhysRevLett.108.117602

M3 - Article

SN - 0031-9007

VL - 108

JO - Physical Review Letters

JF - Physical Review Letters

IS - 11

M1 - 117602

ER -

Subband structure of a two-dimensional electron gas formed at the polar surface of the strong spin-orbit perovskite KTaO3

Abstract

Access to Document

Fingerprint

Projects

Fellowship - Unspent EPSRC Balance: Fellowship - Unspent Funds

Topological Protection and NonEquilibriu: Topological Protection and NonEquilibrium States in Strongly Correlated Electron Systems

Cite this

Subband structure of a two-dimensional electron gas formed at the polar surface of the strong spin-orbit perovskite KTaO₃